JP4088446B2 - Potential difference detection antenna for lightning detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightning detector antenna that detects the occurrence or approach of lightning, and in particular, measures a potential difference between two points in the air and detects the occurrence or approach of lightning from the measured data. It is related with the antenna used by.
[0002]
[Prior art]
A lightning detector that has been generally proposed in the past is that an electromagnetic wave (spatial wave) generated by lightning discharge is detected by an antenna and an alarm is issued. In this type of lightning detector, one antenna is installed in the air and electromagnetic waves are measured (for example, JP-A-7-159546).
[0003]
Japanese Patent Laid-Open No. 5-150053 uses an existing antenna column as an antenna, and attaches a high-voltage lightning sensor using a ferrite core to the antenna, and detects a lightning approach from the output to detect a lightning alarm. A lightning warning device has been proposed.
[0004]
On the other hand, the applicant of this application has proposed a lightning detector in Japanese Patent Application Laid-Open No. 1-267490 that detects the occurrence or approach of lightning by measuring the potential difference between two points in the air over time. This lightning detector compares the detected potential difference integrated and amplified over a certain time width with the preset potential difference stored in advance, and updates the frequency data indicating the history of the detected potential difference when the detected potential difference exceeds the set potential difference. The updated frequency data is compared with a pre-stored registered pattern to output a detection signal. FIG. 2 of the publication shows two lines for measuring the potential at two points in the air. An antenna is shown.
[0005]
[Problems to be solved by the invention]
The present invention obtains an antenna for a lightning detector that detects the occurrence or approach of lightning by measuring the potential difference between two points in the air over time, and is particularly small, easy to manufacture and install, and durable. An object of the present invention is to obtain the above-mentioned antenna for a lightning detector that is high and can accurately detect the occurrence and approach of lightning.
[0006]
[Means for Solving the Problems]
In the potential difference detection antenna according to the present invention, two elongated cylindrical detectors 1 and 2 are arranged at the tip of one support column 7 with an interval in the axial direction. These detectors are made of a conductive material, and a preferred material is a chrome-plated brass pipe or a chrome-plated aluminum pipe. These detectors are fixed to the support column 7 while being insulated from each other. When the support column 7 is an insulating material such as wood or a synthetic resin material, the detectors 1 and 2 can be directly fitted and fixed to the support column. When the column 7 is a conductive material such as a stainless steel pipe, the detection bodies 1 and 2 are held via the insulating spacers 3 and 4 fitted to the column. It is particularly preferable that the spacers 3 and 4 are provided at the upper and lower ends of the cylindrical detectors 1 and 2 so as to hold the elongated cylindrical detectors so as not to contact the support column 7. In this case, if the outer diameter of the spacer 3 at the upper end of each detection body is made larger than the outer diameters of the detection bodies 1 and 2 to form a ridge, rainwater between the spacer 3 and the detection bodies 1 and 2 is formed. Can be prevented, and the durability of the antenna is improved.
[0007]
The two detectors 1 and 2 are arranged on the same axis at a predetermined interval. Therefore, it is most reasonable to fix these detectors in a state where they are inserted into the column 7. The closer the distance L between the two detectors 1 and 2 is, the smaller the antenna can be made. However, since the distance between the two points for detecting the potential is narrowed, the detection accuracy is lowered. The interval that satisfies both the requirements for miniaturization and detection accuracy is about 200 mm in the experiments of the present inventors. The length in the axial direction of the detection bodies 1 and 2 at this time is appropriate to be about 400 mm, and by fixing the two detection bodies 1 and 2 to the tip of a support 3 to 4 m from the ground, it is small and good. An antenna with a thunder detection function can be obtained.
[0008]
The potential detected by the detectors 1 and 2 is input to the electronic device for potential difference detection through the signal lines 8 and 9. When a metal pipe is used as the support column 7, a structure in which the shield coating 9 of the insulated shield cable inserted through the pipe is connected to the lower detection body and the core wire 8 of the cable is connected to the upper detection body is preferable.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram schematically showing the most preferred embodiment of the present invention. Reference numeral 7 is a support made of stainless steel pipe, and is erected at a height of 3 to 4 m above the ground. The detection bodies 1 and 2 are brass pipes having an outer diameter of 50 mm and a length of 400 mm that are chrome-plated, and upper and lower ends thereof are held by insulating spacers 3 and 4 made of synthetic resin fitted to the support column 7. The center of the detection bodies 1 and 2 and the center of the support column 7 coincide with each other, and the distance L between the lower end of the upper detection body 1 and the upper end of the lower detection body 2 is 200 mm.
[0010]
The spacers 3 and 4 are disk-shaped, and the outer diameter of the insulating spacer 3 holding the upper end of each detection body is larger than the outer diameter of the detection bodies 1 and 2, so that the outer periphery thereof is the detection bodies 1 and 2. It protrudes in the shape of a bowl at the top.
[0011]
An insulating shield cable is inserted into the support column 7, the shield coating 9 is connected to the lower detection body 2, and the core wire 8 is connected to the upper detection body 1. This insulated shield cable is drawn out from the lower end of the support column 7, and the shield coating 9 and the core wire 8 serve as two communication lines and are connected to an electronic device for potential difference detection via an interface circuit (not shown).
[0012]
【The invention's effect】
The above-described potential difference detection antenna of the present invention has a simple structure and is compact, and therefore can be provided at low cost, and is easy to install and highly durable. The potential difference detection antenna of the present invention measures the potential difference between two points in the air over time and uses it as a lightning detector antenna to detect the occurrence or approach of lightning from its history, thereby generating lightning. There is also an effect that the approach can be detected with certainty.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of a potential difference detection antenna according to the present invention.
1,2 Detector
3,4 Insulating spacer 7 Strut 8 Core wire 9 Shield coating L Distance length

Claims (4)

A column (7) made of an insulating material, and two cylindrical detectors (1, 2) made of a conductive material insulated and fixed to each other in a state of being inserted through the column at a predetermined interval in the longitudinal direction; A potential difference detection antenna for a lightning detector, comprising two signal lines (8, 9) respectively connected to these detectors. A support (7) made of a conductive material and a conductor 2 insulated from each other and fixed in a state of being inserted into the support through an insulating spacer (3,4) at a predetermined interval in the longitudinal direction. A potential difference detection antenna for a lightning detector, comprising a plurality of cylindrical detectors (1, 2) and two signal lines (8, 9) respectively connected to these detectors (1, 2). The potential difference detection antenna according to claim 1 or 2, wherein the detection body is a chromium-plated brass pipe or a chrome-plated aluminum pipe. The potential difference detection antenna according to claim 1, wherein the two signal lines are a core wire of an insulated shield cable and a shield coating.

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